[Evaluating the effectiveness of HIV/syphilis joint self-testing in promoting syphilis testing among men who have sex with men].

Objective: To evaluate the effectiveness of HIV/syphilis joint self-testing in promoting syphilis testing among men who have sex with men (MSM). Methods: In July 2019, the research participants were recruited through the Danlan website (https://www.danlan.org). Participants who met the selection criteria, and were randomly assigned into one of the three study groups (1∶1∶1) including HIV/syphilis joint self-testing group and lottery incentive self-testing group and control group. Self-test reagents were mailed to HIV/syphilis joint self-testing group and lottery incentive self-testing group, and the subjects in control group were encouraged to go to offline locations for testing. One month later, follow-up was conducted to evaluate the differences in the testing rates of syphilis among the three groups. Results: A total of 145 subjects were included in this study, including 48 in control group, 49 in HIV/syphilis joint self-testing group and 48 in lottery incentive self-testing group. During the follow-up period, the self-testing rate of syphilis was 74.4% (32/43) in HIV/syphilis joint self-testing group, 70.0% (28/40) in lottery incentive self-testing group and 36.4% (16/44) in control group. Multivariate logistic analysis revealed that the proportions of syphilis testing in HIV/syphilis joint self-testing group and lottery incentive self-testing group were 5.38 (95%CI: 2.06-14.04) times and 4.54 (95% CI: 1.75-11.74) times higher than that in control group during the follow-up period. Conclusions: HIV/syphilis joint self-testing and lottery-incentives-prompted self-testing significantly increased the testing rate of syphilis in MSM, respectively. HIV/syphilis joint self-testing is feasible for promotion.